From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 19538 invoked by alias); 14 Jul 2010 21:48:03 -0000 Received: (qmail 19519 invoked by uid 22791); 14 Jul 2010 21:48:02 -0000 X-SWARE-Spam-Status: No, hits=-1.8 required=5.0 tests=AWL,BAYES_00,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from mail.codesourcery.com (HELO mail.codesourcery.com) (38.113.113.100) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 14 Jul 2010 21:47:58 +0000 Received: (qmail 24857 invoked from network); 14 Jul 2010 21:47:56 -0000 Received: from unknown (HELO ?84.152.203.213?) (bernds@127.0.0.2) by mail.codesourcery.com with ESMTPA; 14 Jul 2010 21:47:56 -0000 Message-ID: <4C3E3078.7020706@codesourcery.com> Date: Wed, 14 Jul 2010 21:48:00 -0000 From: Bernd Schmidt User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.10) Gecko/20100625 Thunderbird/3.0.5 MIME-Version: 1.0 To: Jeff Law CC: GCC Patches Subject: Re: Emit more REG_EQUIV notes for function args (PR42235) References: <4C3D9C06.60901@codesourcery.com> <4C3E07EF.1030306@redhat.com> In-Reply-To: <4C3E07EF.1030306@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org X-SW-Source: 2010-07/txt/msg01200.txt.bz2 On 07/14/2010 08:54 PM, Jeff Law wrote: > In theory, given the REG_EQUIV note we ought to get an entry in > reg_equiv_mem, which the code I'm working on knows it can use instead of > shoving the pseudo into a stack slot. Effectively, my code will > rematerialize the argument from the equivalent memory location > regardless of the number of uses. Reload can do that already, I think, but it's not prepared to handle a (zero_extend (mem)) inside a REG_EQUIV note. That should be reasonably trivial to add if the reg is never set other than in the initializing insn. Bernd